Hoisting device and nuclear fuel assembly transportation container

Abstract

The utility model discloses a hoisting device and a nuclear fuel assembly transportation container, the hoisting device is arranged on the nuclear fuel assembly transportation container and comprises a lifting lug and a fastener, and the lifting lug is connected to the nuclear fuel assembly transportation container through the fastener. Compared with the prior art, the hoisting device of the nuclear fuel assembly transportation container disclosed by the utility model has the advantages that a welding seam is omitted, so that an exposed area does not need to be reserved around the lifting lug, and the radiation protection performance of the nuclear fuel assembly transportation container is effectively ensured. Moreover, the fastener is detachably connected with the transportation container, the tightening torque of the fastener can be checked regularly, the fastener can be screwed out to be integrally replaced, and a hoisting test of the nuclear fuel assembly transportation container does not need to be carried out, so that the operation complexity of operators can be reduced, and the personal safety of the operators can be protected.

Description

Technical Field

[0001] The utility model belongs to the technical field of nuclear fuel transportation equipment, in particular to a hoisting device and a nuclear fuel assembly transportation container. Background Art

[0002] Irradiated nuclear fuel assemblies have high radioactivity. In order to achieve radiation shielding function, neutron shielding materials are usually arranged on the outer layer of the irradiated nuclear fuel assembly transport container. The lifting lugs are important load-bearing components of the irradiated nuclear fuel assembly transport container and have very high safety factor requirements.

[0003] Existing irradiated nuclear fuel assembly transport containers have their lifting lugs connected to the container body by welding. To ensure safe handling of transport containers, relevant international and domestic safety standards require regular lifting tests and non-destructive testing. However, this welding method requires the weld seam to be exposed to facilitate non-destructive testing, which encroaches on the space available for neutron shielding material, compromising the radiation shielding performance of the transport container.

[0004] Therefore, how to ensure the radiation protection performance of nuclear fuel assembly transport containers while reducing the complexity of operations for operators and protecting the personal safety of operators is a technical problem that technical personnel in this field urgently need to solve. Utility Model Content

[0005] In view of this, the purpose of the present invention is to provide a lifting device that can not only ensure the radiation protection performance of the nuclear fuel assembly transport container, but also reduce the complexity of the operator's operation and protect the operator's personal safety.

[0006] Another object of the present invention is to provide a nuclear fuel assembly transport container.

[0007] To achieve the above objectives, the present invention provides the following technical solutions:

[0008] A lifting device is provided on a nuclear fuel assembly transport container and comprises a lifting lug and a fastener. The lifting lug is connected to the nuclear fuel assembly transport container via the fastener.

[0009] Optionally, the fastener is a bolt.

[0010] Optionally, there are at least two bolts.

[0011] Optionally, the fitting clearance between the lifting ear and the neutron shield is at least 20 mm.

[0012] Optionally, the lifting ear includes a first body portion and a raised portion, the first body portion is connected to the nuclear fuel assembly transport container, and the top surface of the raised portion is higher than the top surface of the neutron shielding body.

[0013] Optionally, a groove adapted to the first body portion is provided on the nuclear fuel assembly transport container, and the first body portion is loosely fitted in the groove.

[0014] Optionally, the top surface of the protrusion is further provided with an anti-loosening portion, and both ends of the anti-loosening portion extend out of the protrusion by preset lengths at both ends respectively.

[0015] Optionally, the lifting ear includes a second body portion and an inner recess, the second body portion is connected to the nuclear fuel assembly transport container, the inner recess is arranged in the second body portion, and the inner recess extends a preset distance from the top end surface of the second body portion toward the bottom end surface.

[0016] Optionally, the cross-section of the inner concave portion is rectangular, circular, or triangular;

[0017] The inner concave portion is further provided with a slot or a step connected to the sling.

[0018] A nuclear fuel assembly transport container comprises the lifting device as described in any one of the above.

[0019] As can be seen from the above technical solution, compared to the prior art, the lifting device for the nuclear fuel assembly transport container disclosed in this utility model eliminates welds, eliminating the need for exposed areas around the lifting lugs, thereby effectively ensuring the radiation protection performance of the nuclear fuel assembly transport container. Furthermore, the fasteners are detachably connected to the transport container, allowing for regular inspection of the fastener tightening torque and complete replacement of the fasteners by unscrewing them, eliminating the need for lifting tests of the nuclear fuel assembly transport container. This not only reduces operator complexity but also protects the operator's personal safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are merely embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying any creative work.

[0021] Figure 1 A cross-sectional view of the mounting structure of the lifting lug provided in the prior art;

[0022] Figure 2 A cross-sectional view of the installation structure of a hoisting device provided by one embodiment of the present utility model;

[0023] Figure 3 This is a cross-sectional view of the installation structure of a lifting device provided by another embodiment of the present utility model.

[0024] Description of reference numerals:

[0025] 01-lifting lug; 02-transport container; 03-neutron shield; 04-weld;

[0026] 100 - lifting ear; 101 - first main body; 102 - raised portion; 103 - second main body; 104 - recessed portion; 200 - fastener; 300 - nuclear fuel assembly transport container; 400 - neutron shield; 500 - gap. DETAILED DESCRIPTION

[0027] Irradiated nuclear fuel assemblies are highly radioactive, so a neutron shield 03 is typically placed outside the transport container 02 to provide radiation shielding. Loading the irradiated nuclear fuel assemblies into the transport container 02 and transporting the container involve numerous operations such as flipping and lifting the entire container. Lifting lugs 01 are crucial load-bearing components, requiring a high safety factor. Their load-bearing capacity must be significantly greater than the weight of the transport container itself.

[0028] The lifting lug 01 of the existing transport container 02 is connected to the container body by welding. For details, please refer to Figure 1 To ensure safe operation of transport container 02, relevant international and domestic safety standards require regular lifting tests and non-destructive testing. According to relevant international and domestic standards, non-destructive testing of weld 04 typically utilizes visual inspection (VT) and liquid penetrant (PT) methods. To facilitate inspection of weld 04, the area surrounding the lifting lug weld must be exposed. Without neutron shielding material, the radiation dose rate around the lifting lug increases significantly, making it the weakest area of the entire transport container's radiation shielding.

[0029] In order to reduce the negative impact of this type of lifting ear 01 design, that is, the reduction in radiation shielding capability due to the partial absence of the neutron shielding body 03 in the circumferential part of the lifting ear 01, the radiation protection capability of the circumferential part of the lifting ear 01 can be enhanced by filling the part where the lifting ear 01 is located with neutron shielding material, so as to minimize the negative impact of the current lifting ear design. The first treatment method currently adopted by the transport container 02 is to fill the part where the lifting ear is located with neutron shielding material to enhance the radiation protection capability of the circumferential part where the lifting ear 01 is located. However, adding the neutron shielding body 03 to the circumferential part where the lifting ear 01 is located will cause the welding part of the lifting ear 01 to be buried by the neutron shielding material, making it impossible to perform non-destructive inspection of the weld 04.

[0030] Another solution is to add a removable metal ring to the container barrel where the lifting lug 01 is located. Considering the metal's neutron shielding effect and its inherent strength requirements, the metal ring needs to be of a certain thickness. This shortens the protruding portion of the lifting lug 01, making it shorter than the width of the load-bearing part of the sling. This prevents the sling from engaging the lifting lug, and prevents the container from being lifted or turned. Therefore, whenever the container 02 needs to be lifted or turned, the metal ring must also be removed. This increases the complexity of the operation and the risk of radiation exposure to the operator. The heavy weight of the metal ring requires additional lifting equipment, and the risk of collision increases during assembly and disassembly.

[0031] What needs to be explained is:

[0032] Irradiation: Exposure to radiation from radioactive elements.

[0033] Nuclear fuel: Fissionable nuclear material in component form for loading into the core of a civilian nuclear power reactor or research reactor.

[0034] Assembly: A group of components and related parts that are loaded into and later removed from a reactor core as a unit.

[0035] Lifting lug: A load-bearing component installed on equipment for lifting.

[0036] Dose rate: The energy deposited on an object by radiation per unit time.

[0037] In view of this, the core of the present invention is to provide a lifting device that can not only ensure the radiation protection performance of the nuclear fuel assembly transport container, but also reduce the complexity of the operator's operation and protect the operator's personal safety.

[0038] Another core of the present invention is to provide a nuclear fuel assembly transport container.

[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. Please refer to Figures 2 to 3 .

[0040] The lifting device disclosed in the embodiment of the present utility model is arranged on a nuclear fuel assembly transport container 300 and includes a lifting lug 100 and a fastener 200 . The lifting lug 100 is connected to the nuclear fuel assembly transport container 300 via the fastener 200 .

[0041] Compared to the prior art, the lifting device for the nuclear fuel assembly transport container 300 disclosed in the embodiment of the present invention eliminates welds, eliminating the need for exposed areas around the lifting lugs 100, thereby effectively ensuring the radiation protection performance of the nuclear fuel assembly transport container 300. Furthermore, the fastener 200 is detachably connected to the transport container 300, allowing for regular inspection of the tightening torque of the fastener 200 and for complete replacement by unscrewing the fastener 200. This eliminates the need for hoisting tests on the nuclear fuel assembly transport container 300, thereby reducing operator complexity and protecting their personal safety.

[0042] The embodiment of the present invention does not limit the specific structure of the fastener 200. As long as the structure meets the requirements of the present invention, it is within the protection scope of the present invention.

[0043] The fastener 200 may be a bolt, a screw, a pin, etc., and those skilled in the art may select the fastener according to actual needs.

[0044] As one of the preferred embodiments, the fastener 200 disclosed in the embodiment of the present utility model is preferably a bolt.

[0045] The embodiments of the present invention do not specifically limit the number of bolts. As long as the number meets the use requirements of the present invention, it is within the protection scope of the present invention.

[0046] As a preferred embodiment of the present invention, the number of bolts disclosed in the embodiment of the present invention is at least two.

[0047] As a further example, the clearance 500 between the lifting lug 100 and the neutron shield 400 disclosed in the embodiment of the present invention is at least 20 mm. This arrangement minimizes the area encroached upon by the lifting lug 100 within the neutron shield 400, significantly reducing the impact on the radiation protection capability of the nuclear fuel assembly transport container.

[0048] The embodiment of the present invention does not limit the specific structure of the lifting ear 100. As long as the structure meets the use requirements of the present invention, it is within the protection scope of the present invention.

[0049] As one example, please refer to Figure 2 The lifting lug 100 disclosed in the embodiment of the present invention includes a first body portion 101 and a raised portion 102. The first body portion 101 is connected to the nuclear fuel assembly transport container 300, wherein the top surface of the raised portion 102 is higher than the top surface of the neutron shield 400. This arrangement not only facilitates protection against radioactive rays without requiring additional radiation protection structures, but also avoids interference when connecting to a lifting device, thus expanding the range of lifting devices available.

[0050] The nuclear fuel assembly transport container 300 is provided with a groove adapted to the first body portion 101 of the lifting lug 100 , and the first body portion 101 is loosely fitted into the groove.

[0051] In order to prevent the sling from loosening when mating with the sling, the top surface of the protrusion 102 disclosed in the embodiment of the present invention is further provided with an anti-loosening portion, the two ends of which extend out of the two ends of the protrusion 102 by a preset length. This arrangement can effectively prevent the sling from loosening when mating with the sling.

[0052] Of course, as another example, please refer to Figure 3 The lifting ear 100 disclosed in the embodiment of the present invention includes a second body portion 103 and an inner recess 104. The second body portion 103 is connected to the nuclear fuel assembly transport container, and the inner recess 104 extends a preset distance from the top end surface of the second body portion 103 toward the bottom end surface.

[0053] The embodiment of the present invention does not limit the specific structure of the inner recess 103. The cross-section of the inner recess 103 can be rectangular, circular, or triangular. As long as the structure meets the use requirements of the present invention, it is within the protection scope of the present invention.

[0054] In order to fit more tightly with the sling and avoid loosening, the inner recess 103 disclosed in the embodiment of the present invention is further provided with a slot or step connected to the sling. Such a setting further enhances the connection strength between the lifting lug 100 and the sling.

[0055] An embodiment of the utility model further discloses a nuclear fuel assembly transport container, comprising the lifting device disclosed in any one of the above embodiments.

[0056] Since the nuclear fuel assembly transport container 300 adopts the lifting device disclosed in the above embodiment, the nuclear fuel assembly transport container 300 has the technical advantages of the lifting device disclosed in the above embodiment, and the embodiment of the present utility model will not describe them one by one.

[0057] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprises" or any other variation thereof is intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0058] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0059] The above description of the disclosed embodiments will enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A lifting device, provided on a nuclear fuel assembly transport container, characterized in that: The utility model comprises a lifting lug and a fastener, wherein the lifting lug is connected to the nuclear fuel assembly transport container through the fastener.

2. The hoisting device according to claim 1, characterized in that: The fastener is a bolt.

3. The hoisting device according to claim 2, characterized in that: There are at least two bolts.

4. The hoisting device according to claim 1, characterized in that: The fitting clearance between the lifting lug and the neutron shield is at least 20 mm.

5. The hoisting device according to claim 4, characterized in that: The lifting lug includes a first body portion and a raised portion, wherein the first body portion is connected to the nuclear fuel assembly transport container, and a top surface of the raised portion is higher than a top surface of the neutron shielding body.

6. The hoisting device according to claim 5, characterized in that: The nuclear fuel assembly transport container is provided with a groove adapted to the first body portion, and the first body portion is loosely fitted in the groove.

7. The hoisting device according to claim 5, characterized in that: The top end surface of the protrusion is further provided with an anti-loosening portion, and both ends of the anti-loosening portion extend out of the protrusion by preset lengths at both ends.

8. The hoisting device according to claim 1, characterized in that: The lifting ear includes a second body portion and an inner recessed portion, the second body portion is connected to the nuclear fuel assembly transport container, the inner recessed portion is arranged on the second body portion, and the inner recessed portion extends a preset distance from the top end surface of the second body portion toward the bottom end surface.

9. The hoisting device according to claim 8, characterized in that: The cross section of the inner concave portion is rectangular, circular, or triangular; The inner concave portion is further provided with a slot or a step connected to the sling.

10. A nuclear fuel assembly transport container, characterized in that: Comprising the lifting device according to any one of claims 1 to 9.

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